[Skiboot] [PATCH V2] VAS: Alloc IRQ and port address for each VAS instance

[Oliver O'Halloran]

On Sat, Oct 12, 2019 at 8:44 PM Haren Myneni <haren at linux.vnet.ibm.com> wrote:
>
>
> Setup IRQ and trigger port for each VAS instance. Export these
> values through device-tree with 'interrupts' and 'ibm,vas-port'
> properties in each VAS device node. Kernel setup IRQ and register
> port address for each send window.
>
> Signed-off-by: Sukadev Bhattiprolu <sukadev at linux.vnet.ibm.com>
> Signed-off-by: Haren Myneni <haren at us.ibm.com>
> ---
> Changes from V1:
> - Use standard 'interrupts' property as suggested by Oliver
>
>
> diff --git a/doc/device-tree/vas.rst b/doc/device-tree/vas.rst
> index 438e45f..7c11c78 100644
> --- a/doc/device-tree/vas.rst
> +++ b/doc/device-tree/vas.rst
> @@ -18,6 +18,12 @@ Each VAS node contains: ::
>
>    ibm,vas-id: unique identifier for each instance of VAS in the system.
>
> +  ibm,vas-port: Port address for the interrupt.
> +
> +  interrupts: <IRQ# level> for this VAS instance.
> +
> +  interrupt-parent: Interrupt controller phandle.
> +
>    reg: contains 8 64-bit fields.
>
>          Fields [0] and [1] represent the Hypervisor window context BAR
> diff --git a/hw/vas.c b/hw/vas.c
> index 212da0e..be006f6 100644
> --- a/hw/vas.c
> +++ b/hw/vas.c
> @@ -6,6 +6,8 @@
>  #include <phys-map.h>
>  #include <xscom.h>
>  #include <io.h>
> +#include <xive.h>
> +#include <interrupts.h>
>  #include <vas.h>
>
>  #define vas_err(__fmt,...)     prlog(PR_ERR,"VAS: " __fmt, ##__VA_ARGS__)
> @@ -24,6 +26,7 @@ struct vas {
>         uint64_t        xscom_base;
>         uint64_t        wcbs;
>         uint32_t        vas_irq;
> +       uint64_t        vas_port;
>  };
>
>  static inline void get_hvwc_mmio_bar(int chipid, uint64_t *start, uint64_t *len)
> @@ -402,6 +405,9 @@ static void create_mm_dt_node(struct proc_chip *chip)
>
>         dt_add_property(dn, "ibm,vas-id", &vas->vas_id, sizeof(vas->vas_id));
>         dt_add_property(dn, "ibm,chip-id", &gcid, sizeof(gcid));
> +       dt_add_property_cells(dn, "interrupts", vas->vas_irq, 0);
> +       dt_add_property_cells(dn, "interrupt-parent", get_ics_phandle());
> +       dt_add_property_u64(dn, "ibm,vas-port", vas->vas_port);
>  }
>
>  /*
> @@ -423,6 +429,25 @@ static void disable_vas_inst(struct dt_node *np)
>         reset_north_ctl(chip);
>  }
>
> +static int vas_setup_irq(struct proc_chip *chip)
> +{
> +       uint32_t irq;
> +       uint64_t port;
> +
> +       irq = xive_alloc_ipi_irqs(chip->id, 1, 64);
> +       if (irq == XIVE_IRQ_ERROR)
> +               return -1;
> +
> +       vas_vdbg("trigger port: 0x%p\n", xive_get_trigger_port(irq));
> +
> +       port = (uint64_t)xive_get_trigger_port(irq);
> +
> +       chip->vas->vas_irq = irq;
> +       chip->vas->vas_port = port;
> +
> +       return 0;
> +}
> +
>  /*
>   * Initialize one VAS instance and enable it if @enable is true.
>   */
> @@ -452,6 +477,9 @@ static int init_vas_inst(struct dt_node *np, bool enable)
>                                 init_rma(chip))
>                 return -1;
>
> +       if (vas_setup_irq(chip))
> +               return -1;

As I said on the last revision, why are you doing an early exit if
vas_setup_irq() fails? The existing code doesn't provide an interrupt
and it seems to work just fine...

> +
>         create_mm_dt_node(chip);
>
>         prlog(PR_INFO, "VAS: Initialized chip %d\n", chip->id);
>
>